1. Field of the Invention
This invention relates to medical devices and, in particular, to surgical instruments relating to suturing devices and techniques. More particularly this invention relates to devices and methods for passing sutures through tissue to be sutured.
2. Description of the Prior Art
It is often necessary in both open and endoscopic surgical procedures to use sutures to ligate, join or otherwise treat tissue. Generally, suture needles (with attached suture material) are grasped either manually or by forceps and passed through the desired work site so a knot can be tied. While the procedures are fairly straightforward in open surgery where most suture sites are readily accessible, in instances where access to the work site is not readily available and in endoscopic procedures the surgeon must use auxiliary devices to be able to grasp needles and pass them through desired tissue. The term "endoscopic" is used herein to mean surgical procedures performed through elongated cannulae inserted into a body through small incisions or punctures.
Several devices and methods for surgical repair requiring the passing of needles and sutures to distant (but not necessarily endoscopic) locations have already been developed. For example, U.S. Pat. No. 4,781,190 (Lee) discloses a method and a two-ended needle enabling arthroscopic suturing of the interior of a joint. The two-ended needle may be either straight or curved and has an eyelet intermediate the ends of the needle. Alternately passing the ends of the needle through tissue to be sutured enables a suture, passing through the eyelet of the needle, to be woven through the tissue.
U.S. Pat. No. 4,441,497 (Paudler) discloses a suture passer having a plurality of flexible elongated members joined at their ends, these ends being sharpened enough to pass through desired tissue sites. Pushing the ends toward each other opens up spaces between the members into which one or more sutures may be placed. Moving the ends of the flexible members away from each other closes up the spaces to thereby grip the sutures so the ends of the flexible members and, consequently, the sutures, may be passed through desired suture sites.
Each of the foregoing suture passing devices has disadvantages associated with it and it is an object of this invention to overcome these disadvantages. In particular, it is an object of this invention to produce a suture passing device which is more flexible than prior art devices while also being strong enough to be directed to work sites deep within the body. The invention is flexible enough to be directed in any desired direction and strong enough to pull sutures from outside the body to the desired work site. The suture may then be tied and the suture knot advanced to the suture site by known techniques.
Other devices known to advance suture material directly to a work site are shown in U.S. Pat. Nos. 4,890,615 (Caspari et al.) and 4,923,461 (Caspari et al.), both of which are incorporated by reference herein. The Caspari devices and others like them advance suture material by passing it through one or more rollers, one of which is turned by the user to propel the suture beyond the nip of the rollers. While suitable for mono-filament suture, such roller-type devices may unravel multi-stranded suture which is preferable for certain applications. Accordingly, a means of passing multi-stranded suture material via roller-type suture passing devices would be desirable. It is an object of this invention to produce a suture passing device or shuttle that is usable with roller-type suture advancing devices and suitable for passing multi-stranded suture with such devices.